This invention relates generally to medication dispensing devices, and more particularly, relates to devices for application of anal medication.
Anal medication, such as hemorrhoidal ointment and foam have been administered by inserting syringe-type devices through the anus into the rectal canal where the medication is discharged. Since only the circumferential area immediately inside the anus extending for approximately 3 centimeters into the lower rectal vault is supplied with sensory perception, the medication dispensed by prior art syringe devices has generally been wasted in the nonsensory area located deeper into the rectal canal. Such deeper areas of the rectal canal have only sympathatic and para sympathatic nerves. Typical prior art syringe devices supplied with hemorrhoidal ointments and foam such as Americaine.RTM. and Proctofoam.RTM., respectively, have an opening in the terminal end of the dispensing tube through which the bulk of the medication is discharged into the rectal canal. Even when such tubes have been provided with lateral openings, the resulting limited volume of medication discharged through the lateral openings impacts too remote from the lower rectal vault for application directly to the sensory anal area where the base of internal hemorrhoids may be located.
Other syringe-type devices for insertion into body orifices are described in U.S. Pat. Nos. 719,487, 1,127,201, 2,036,218 and 3,593,713, but none of these devices is designed to provide discharge of medication to the limited sensory area immediately inside the anus. For example, U.S. Pat. No. 3,593,713 describes a catheter tube having an area of perforations along its length and an elastic casing or sheath which can be rolled back to expose the desired length of perforated area. The length of perforated area is controlled to suit requirements for discharge of medication along different lengths to accommodate, for example, variation in the length of the urethra. The catheter is also provided with an inflatable chamber located beyond the perforated area of the barrel and rearwardly of its tip, so that when the chamber is inflated, it will engage the wall within the body orifice in which the catheter is inserted to retain the catheter in place.
U.S. Pat. No. 1,127,201 describes a syringe for use as a douche which has perforations in the end and along the length of the barrel. A rubber guard can be adjustably positioned along the length of the barrel to limit penetration into the womb. In use, the apex of the guard limits the penetrating length of the syringe to between 2 and 4 inches. None of the syringes described in these patents provides structure to specifically limit discharged medication to the sensory area immediately within the anus.